Forum > GPU crunching

BOINC 6.6.20 x64 does not run on 2 GPUs on Win 7

<< < (3/5) > >>

FalconFly:
lol

Not realizing two GTX295 would already steal some 3.5GB of upper memory, the System crashed hard and I had to remove one of the GTX295 again. With only some ~400MB usable RAM remaining, operation of the GTX295 pair is basically useless under a 32bit OS. I simply forgot that.

So right now I'm down to one GTX295 per System as it persistently failed unter WinXP 32 (insufficient address space), Vista 64 (Driver bug) and Win7 64 (Driver bug).

I've tried plugging in multiple Monitors as some suggested in the Forums, but that didn't change anything either.

It is beyond me how people manage to operate more than one GTX295 with the 185.85 Driver and due to time I've given up on that project. I've tried hard for a whole week but all to no avail.

Raistmer:
You could try to use other GPU for PhysX instead of plugging monitor. This officially recommended from nVidia (worth to look their forums btw for GPU issues).

FalconFly:
I tried enabling Physx but that did not change anything unfortunately.

The only working Config I found for 2xGTX295 was WinXP32 (couldn't work due to RAM limitations, but otherwise would have).

I'm now down to one GTX295 per System, as this was the only config I could get to work after over a week of intense troubleshooting (two Systems run XP32, one System runs Vista64)

Seeing both Vista64 and Win7 64 completely fail to have the Win64 185.85WHQL Driver report more than 2 GPUs to BOINC for CUDA use, I'm almost confident it's a Driver issue.
The same occured when I enabled the CUDA capable IGP; point blank fresh install with all needed Service Pack and System Drivers resulted a fresh BOINC 6.6.20 (32bit and 64bit) Install to see only the IGP, despite upto 2 GTX295 being active and seen by the Driver panel.

I also found some serious SLI performance problems with the Win64 185.85WHQL Driver under DX9 and especially OpenGL, all cards were working fine (at least the hardware), supporting my suspicion that there's something buggy buried in that Driver.

The 32bit 185.85WHQL Driver apparently does not have any such limitation, under WinXP32 immediately reported all 4 GPUs to BOINC as it should (useless with <400MB usable RAM remaining, but technically it did not have any problems).

efmer (fred):
Still no luck with the 295, because I have the same problem.

jockmacmad:
There are 2 potential fixes for this and it's not just Windows 7 but x64 Vista as well.

There is a new command on BOINC in cc_config.xml to avoid the incorrect memory sizing on the second GPU or you can add LimitVideoPresentSources to the registry for th card. This stops the need for any dummy VGA adapter etc. The problem I had is due to Vista and Windows 7 only enabling the GPU if there is a device connected to the VGA/DVI port.

The xml to add to cc_config.xml is:-
<cc_config>
<options>
<use_all_gpus>1</use_all_gpus>
</options>
</cc_config>

cc_config.xml file definition is here.
Full solution for LimitVideoPresentSources is at the BOINC Forums

Navigation

[0] Message Index

[#] Next page

[*] Previous page